Diminishing feed



'May 10, 1938.

E. D. LA FLEUR DIMINISHING FEED Filed Dec. 21, 1957 4 Sheets-Sheet l May 10, ,1938.

E. D. LA FLEUR DIMINISHING FEED Fi led Dec. 21, 1957 4 Sheets-Sheet 2 0 who May 10, 1938. E. D. LA FLEUR DIMINISHING FEED 4 Sheets-Sheet 3 Filed D86. 21, 195'? I r i May 10, 1938. E. D. LA FLEUR Y DIMINISHING FEED Filed Dec. 21, 1957 4 Sheets-Sheet 4 MXM Patented May 10, 1938 2,116,794

NETED s'rares PATENT ori ice DIMINISHING FEED Elphege D. La Fleur, Lancaster, Mass.

Application December 21, 1937, Serial No. 181,002

Claims. (01. 5192) This invention relates to a feed for a grinding rotation of the gear l9, which is fixed to the screw or milling machine or automatic lathe, or the shaft 20, rotates that screw shaft and, through like, in which the feed will be diminished at the a screw threaded nut 2| carried by a slide 22, end of the stroke. adjusts the slide back and forth. This adjust- The principal objects of the invention are to ment is made before the operation of the machine '6 provide an auxiliary piston and cylinder with a d is ep of Cou in Constant position during shaft operated by the piston and having an ecthat operation. Furthermore, this renders the centric or cam thereon adapted to engage stops slide 22 practically a part of the bed 10, as they at one or both ends of the stroke to cut down the o not v relatively to each h r ft r h '10 f eed when the grinding wheel or cutting element machine is once adjusted. 10 is coming to the end of its stroke for purposes Movable relatively to these two parts In and 22 that are obvious; to provide said piston with a is a wheel head 23 carrying a shaft 24 on which is rack and a gear construction on the shaft for supported the grinding wheel 25. This head 23 operating the eccentric cam and to provide a is provided with a protecting skirt 28 and with a slide adjustable along the wheel bed head and hollow separate top 29. In this top is mounted 15 thereafter practically constituting a part of it a shaft 30 parallel to the shaft and having a for supporting the stops used for providing the pair of notches 3| and 32 for a spring pawl 33.

diminishing of feed at the end of the stroke. On the end of the shaft is a graduated hand Other objects and advantages of the invention wheel 34 by which the shaft can be moved back 20 will appear hereinafter. and forth to bring it into either of the positions go Reference is to be had to the accompanying in which the spring pawl is held in one or the drawings, i hich other of the circumferential notches 3| or 32.

Fig. 1 is a sectional view through the table of By this hand wheel the shaft 30 also can be a grinding machine for carrying the work and turned.

5 through the shaft of the grinding wheel to oper- In the position shown a bevel gear 35 on the ate thereon, showing the invention as applied shaft 39 meshes with a bevel gear 36 on a shaft the t 31 at right angles to the shaft 33 and rotates it Fig. 2 is a view, largely diagrammatic, of the by means of the hand wheel. On the end of the same mechanism, showing the course of the liqshaft is a rod 38 passing through a passage 30 old for operating the same hydraulically; in a lever 39 and adjustably connected there- 30 Fig. 3 is a view similar to the lower right hand with by a nut and check nuts 40. This lever 3.) corner of Fig. 2, showing a modification for apis pivoted at 4! on the wheel head 23 and is proplication to another machine; vid-ed with an arm 42 which projects into a cir- Fig. 4 is a plan of the same, as indicated by the cular groove in a collar 43 on the shaft 31. In

arrow l in Fig. 3; this way, when the hand wheel 34 is moved back 35 Fig. 5 is an end view as indicated by the arrow from the position shown in Fig. 1 to a position 5 in Fig. 4, and in which the spring pawl 33 will enter the groove Fig. 6 is a diagrammatic view of the same de- 32, the bevel gear 35 will drop back out of mesh vice. and the collar 43 is moved down. Fixed to this The form of the machine to be described first collar, which is free on the shaft 31, is a pinion 40 embodies Figs. 1 and 2 and it also includes mech- M. This pushes the pinion 44 over into a posianism shown in Figs. 3, 4, and 5 except that in tion in which it can mesh with a reciprocating these figures only one stop is shown so that in rack 15, as shown in Fig. 2. describing Figs. 1 and 2, Figs. 3, 4, and 5 will be Leaving this rack for the moment, it will be 15 taken into consideration. noticed that there is an eccentric or cam 46 on The bed 19 of the machine to which this inventhe end of the shaft 31' located between two stops tion is applied carries ways II for a reciprocating 31 and 38 on the slide 22. Between these stops table l2 on which is a rest l3 to which the work is a longitudinal depression or perforation 49 for is to be directly clamped in the usual way. The receiving the nut 53 holding the cam 46 in posimeans for reciprocating this table is not shown ticn and also the end of the shaft 31. When it 50 except that the central cylinder I4 is indicated. is desired, the hand wheel 3 is turned to bring On this bed is mounteda shaft 15 provided with the high portion of the cam 46 around in the hand wheel It for operating it and gauge 11. direction of the arrow against the stop 41 to per- On the other end of this shaft I5 is a gear 18 form the operation of diminishing the feed, as

55 meshing with a gear i9 on a screw shaft 20. The will appear hereinafter. The hand wheel 34 is 55 drawn back to disconnect the feed and at the same time operate the lever 39 to bring the pinion 44 into the path of the rack 45, the results of which will appear later.

After oil under pressure is introduced into a chamber 54, constituting a cylinder, against the head of a stationary piston 55 fixed to the base I0, oil will be driven through a meter valve 56, which can be adjusted as desired, into a cylinder 51 in which the head of the piston is located. It will be noticed that there is a spring 58 behind the head of the piston 5| which is guided and serves to reset that piston.

The novel features having been described, the operation will be described with reference to Fig. 2 which shows also some features that are in a general way in use at the present time. The pipe line 55 is supplied with oil or other operating liquid from a pump 62 through a relief valve 53 which has a connection 54 to a tank. Therefore, in operating the push button 6!] the oil under pressure is sent through this connection from a pipe 65 to a pipe 53, energizing the solenoid operated four-way valve 5|, allowing oil to flow into the cylinder 54. This builds up pressure against the stationary piston 55, forcing the wheel head v23 forward until the eccentric or cam 46 which, it will be remembered, is mounted on the wheel head, hits the stop 41 as illustrated.

The pressure then builds up in the cylinder 5! against the end of the piston which carries the rod 5| and the rack 45. This piston is forced back in the direction indicated by the arrow in Fig. 2. The rack being in mesh with the pinion 44 on the shaft 37 turns the cam or eccentric 46 mounted on the same shaft in the direction of the circular arrow in Fig. 2 against the stop 41. This gives the drive a diminishing feed rate at the end of the stroke. The rate of feed is controlled by the metering valve 56. When the rack comes to the end of its stroke it trips the limit switch 59 to energize the other side of the four-way valve 5|, thus reversing the direction of the oil through a pipe line 13 and bringing the wheel head to the starting position. At the same time the spring 58 moves the piston rod 5| forward. This resets the eccentric or cam 46.

As there are two stops in the form shown in Fig. 2, this action can occur at both ends of the stroke. Meantime, the pressure is held in the forward cutting direction as the oil by-passes from the cylinder 54 to the cylinder 57, during the diminishing feed period. The relief valve 63 holds the ressure in the line 65 slightly under the high pressure limit.

It will be noted that the hand wheel 34 is pulled out to break the mesh between the bevel gears and at the same time it shifts the gear 44 into mesh with the rack 45 for hydraulic feed. The gear 54 is out of mesh with the rack for hand feed when the gears 35 and 36 are in mesh and the hand feed can take place by the turning of the hand wheel 34. The pressure is maintained between the base Hl and the threaded screw 25 at all times, thereby eliminating back lash. The bearings for this screw are mounted on the base Ill. The adjustment of the slide 22 carrying the stops 4'! and 48 is to take up wheel wear and also to provide for working of different diameters. The form shown in Figs. 1 and 2 and described above is to secure diminishing feed of a wheel head at the end of a stroke.

In the form shown in Figs. 3 to 6 the corresponding device is designed for the feed of a table. It is hardly necessary to describe the differences but it will be noted that the feed of the oil is substantially the same and the same reference numerals have been applied to it. In this case the table ID is shown as moving in the direction of the arrow. The plunger 5| with the rack 45 thereon is operating in connection with the pinion 44 and turning the eccentric or cam 46 against a single stop II. The pinion 45 is operated by a hand wheel 12 capable of moving into full and dotted line positions in Fig. 4 to bring it into and out of mesh with the rack 45. The operation is substantially the same as in the other case and the same results are secured, it being understood that the slide 22 shown in the other figures is also to be applied to this in the same way and with the same adjustment or in the equivalent thereof.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. In a speed diminishing device, the combination with a member to be reciprocated, of hydraulic means for moving said member, means for supplying said means with a motive liquid under pressure, a cylinder movable exactly with said member, a single acting piston movable in said cylinder and having a rod projecting therefrom, means for supplying said cylinder with a motive liquid under a measured pressure to move its piston backwardly with respect to the direction of motion of said member near the end of the stroke thereof, and means operated by said piston rod and cooperating with said member for reducing the speed of said member toward the end of its stroke.

2. In a device for diminishing the speed of feed at the end of a stroke, the combination with a machine for grinding or cutting, of a liquid pressure line, a cylinder and piston therein, means for introducing liquid under pressure from said line into said cylinder, said piston being fixed in stationary position and said cylinder being movable to produce the stroke, a second cylinder movable with the first cylinder, a second piston in the second cylinder movable relatively thereto, means for delivering liquid under pressure to the second cylinder to build up a pressure in the second cylinder to move the second piston, a shaft, a cam fixed to said shaft, means for transmitting the straight line motion of the second piston to the shaft and cam as a turning motion, and means whereby, near the end of the stroke, the speed of the stroke will be diminished.

3. In a device for diminishing the speed of feed at the end of a stroke, the combination with a machine for grinding or cutting, of a liquid pressure line, a cylinder and piston therein, means for introducing the liquid under pressure from said line into said cylinder, said piston being fixed in stationary position and said cylinder being movable to produce the stroke, a second cylinder movable with the first cylinder, a second piston in the second cylinder but movable relatively thereto, a metering valve in said line for delivering liquid under pressure to the second cylinder to build up a low pressure in the second cylinder to move the second piston, a shaft, an eccentric or cam fixed to said shaft, means for transmitting the straight line motion of the second piston to the shaft and cam as a turning motion, and a stop fixed with respect to said pistons, whereby near the end of the stroke, the eccentric cam can engage the stop and diminish the speed of the stroke.

4. In a device for diminishing the feed at the end of a fast hydraulic stroke, the combination with a machine for grinding or cutting, of a liquid pressure line, a member to be reciprocated, two cylinders carried by said member, a stationary single acting piston in the first cylinder against which a pressure can be built up to move said member, means for introducing pressure from said line into the first cylinder to move said member, means for introducing liquid under controlled reduced pressure from said line into the second cylinder, a single acting piston in the second cylinder adapted to be moved by the builtup pressure in its cylinder at the end of the stroke, and means operated by the second piston for diminishing the speed of the stroke of said member near the end of the stroke.

5. In a speed diminishing device, the combination with a member to be reciprocated, of hydraulic means for moving said member, means for supplying said means with a motive liquid under pressure, a cylinder movable exactly with said member, a single acting piston movable in said cylinder and having a rod projecting therefrom, means for supplying said cylinder with a motive liquid under a measured pressure to move its piston backwardly with respect to the direction of motion of said member near the end of the stroke thereof, said piston having a rod projecting from said member having a rack thereon. a transverse shaft, a pinion on said shaft adapted to mesh with said rack, whereby the shaft will be turned, a cam or eccentric fixed on said shaft, and a stop fixed with respect to said member, whereby the turning of the cam against the stop will slow down the speed of the stroke.

6. In a speed diminishing device, the combination with a member to be reciprocated, of hydraulic means for moving said member, means for supplying said means with a motive liquid under pressure, a cylinder movable exactly with said member, a single acting piston movable in said cylinder and having a rod projecting therefrom, means for supplying said cylinder with a motive liquid under a measured pressure to move its piston backwardly with respect to the direction of motion of said member near the end of the stroke thereof, said piston having a rod projecting from said member having a rack thereon, a transverse shaft. a pinion on said shaft adapted to mesh with said rack, whereby the shaft will be turned, a cam or eccentric fixed on said shaft, a stop fixed with respect to said member, whereby the turning of the cam against the stop will slow down the speed of the stroke, a limit switch in position to be engaged and closed by the rod at the end of the stroke of the piston rod, and

means controlled by the limit switch for reversing the flow of pressure liquid in the liquid pressure line.

7. In a device for diminishing the speed of a stroke near the end thereof, the combination with a member to be reciprocated and hydraulic means for reciprocating it. of a cylinder mounted on and movable with said member, a single acting piston in said. cylinder, a piston rod fixed to said piston and projecting beyond said member, whereby said piston rod can move independently of said member, a spring in said cylinder under the piston for restoring the piston to normal position after it has been operated, a rack on the piston rod, a transverse shaft having a pinion movable therealong to mesh with the rack or miss it, a cam or eccentric fixed on said shaft, a stop carried by said member against which the cam canbe moved, a bevel gear on said shaft, a second shaft, a bevel gear on the second shaft adapted to mesh with the first named bevel gear, means for moving the second shaft longitudinally to bring the bevel gears out of mesh, and means whereby, when the second shaft is so moved, the pinion will thereby be moved into mesh with the rack.

8. In a device for diminishing the speed of a stroke near the end thereof, the combination with a member to be reciprocated and hydraulic means for reciprocating it, of a piston and piston rod, a rack on the piston rod, a transverse shaft having a pinion movable therealong to mesh withthe rack or miss it, a cam or eccentric fixed on said shaft, a stop carried by said member against which the cam can be moved, a bevel gear on said shaft, a second shaft, a bevel gear on the second shaft adapted to mesh with the first-named bevel gear, means for moving the second shaft longitudinally to bring the bevel gears out of mesh, means whereby, when the second shaft is so moved, the pinion will thereby be moved into mesh with the rack, and a hand wheel on the second shaft, whereby, in one position of the second shaft, the cam can be turned by hand through the hand wheel and, in the other position of the shaft, the cam will be turned by power.

9. In a device for diminishing the speed of a stroke near the end thereof, the combination with a member to be reciprocated and hydraulic means for reciprocating it, of a cylinder carried by said member, a piston in the cylinder carrying a piston rod. a rack on the piston rod, a transverse shaft having a pinion movable therealong to mesh with the rack or miss it, a cam or eccentric fixed on said shaft. stops carried bysaid member against which the cam can be moved, a bevel gear on said shaft, a second shaft. a bevel gear on the second shaft adapted to mesh with the first-named bevel gear. means for moving the second shaft longitudinally to bring the bevel gears out of mesh, means whereby, when the second shaft is so moved, the pinion will thereby be moved into mesh with the rack. and means for adjustably holding the stops relatively to said member and to then fix them thereto in such a way as to eliminate backlash.

10. In a device for diminishing the speed of a stroke near the end thereof, the combination with a member to be reciprocated and hydraulic means for reciprocating it, a transverse shaft having a pinion movable therealong, a cam or eccentric fixed on said shaft, a stop carried by said member against which the cam can be moved. a bevel gear on said shaft, a second shaft, a bevel gear on the second shaft adapted to mesh with. the first-named bevel gear, means for moving the second shaft longitudinally to bring the bevel gears out of mesh, and a hand wheel on the second shaft. whereby, in one position of the second shaft. the cam can be turned by hand through the hand wheel and, in the other position of the shaft, the cam will be turned by power.

ELPHEGE D. LA FLEUR. 

